A multi-functional digital camera having a text shooting mode, in addition to a normal shooting mode, has appeared in the market. The normal shooting mode is a mode in which natural images, such as a normal snaps, are shoot. On the other hand, the text shooting mode is a mode in which text printed on a printing medium, such as a paper, are shoot. The images shoot in the text shooting mode may be then subjected to character recognition etc.
Japanese Patent Application Laid-Open (JP-A) No. 8-125870 discloses a digital still camera having a normal shooting mode and a text shooting mode. The two modes can be switched as desired. The disclosed camera comprises natural image compressing unit for compressing the acquired image data when the normal shooting mode is selected. On the other hand, this camera comprises a text compressing unit (compressing unit suitable to a small-step gray-scaling image) when the text shooting mode is selected. The compressed image data is stored in an external memory. Thus, the image data can be compressed efficiently without deteriorating the image quality in shooting either a natural image or text.
The above conventional digital camera, however, has a problem that it cannot utilize captured image data efficiently. More specifically, the digital camera having the text shooting mode cannot use a captured image directly for facsimile transmission or the like. Thus, in order to use the captured image for facsimile transmission, there is a problem that one has to transfer an image shot by the digital camera to a computer, and finish a procedure including decompression, image conversion, and compression, etc. before the transmission.
Furthermore, a compressing method is determined unambiguously in response to the shooting mode, and for example, in case of shooting a text (encyclopedia, etc.) with a natural image printed therein, if the text is shot in the text mode, it is compressed by a compressing method suitable to a small-step gray scale image, thereby making it impossible to reproduce the natural image portion. Therefore, in order to reproduce the natural image portion, the user has to shoot the text in the normal shooting mode all over again. Hence, the user has to select and use the mode for a specific purpose.